performance-data/bugzilla-data-low.json at main · mozilla/performance-data · GitHub

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{"bugs":[{"component":"Graphics","last_change_time":"2025-04-24T15:29:17Z","op_sys":"Unspecified","keywords":["perf"],"summary":"Stop looking up GLContext symbols for every new window","creation_time":"2017-02-22T23:15:05Z","severity":"S3","priority":"P3","id":1341913,"status":"ASSIGNED"},{"keywords":["perf:pageload"],"last_change_time":"2025-03-21T02:42:31Z","op_sys":"Android","component":"Performance: Navigation","id":1522282,"status":"ASSIGNED","severity":"S3","priority":"P1","creation_time":"2019-01-23T21:52:44Z","summary":"Delayed image loading on low end ARM devices"},{"severity":"S3","priority":"P3","id":1631949,"status":"ASSIGNED","summary":"Investigate merging shader cache files","creation_time":"2020-04-21T20:52:29Z","last_change_time":"2022-10-12T00:08:45Z","op_sys":"Unspecified","keywords":["perf:startup"],"component":"Graphics"},{"priority":"--","severity":"S2","id":2008619,"status":"ASSIGNED","summary":"[meta] Text shaping word cache affects performance on several SP3 tests (particularly TipTap)","creation_time":"2026-01-05T20:54:42Z","op_sys":"Unspecified","last_change_time":"2026-07-14T15:23:29Z","keywords":["meta"],"component":"Graphics: Text"},{"summary":"Poor performance using bookmarks menu with large amounts of bookmarks.","creation_time":"2009-04-01T20:00:41Z","severity":"S3","priority":"P3","status":"NEW","id":486378,"component":"Bookmarks & History","last_change_time":"2023-05-16T02:23:47Z","op_sys":"Windows Vista","keywords":["blocked-ux","perf"]},{"component":"Places","last_change_time":"2025-03-11T07:58:22Z","op_sys":"All","keywords":["main-thread-io","meta","perf","perf:frontend","perf:responsiveness"],"summary":"[meta] Implement an Asynchronous API for opening container query nodes","creation_time":"2009-04-29T22:35:30Z","severity":"N/A","priority":"P3","status":"NEW","id":490714},{"component":"Layout: Columns","keywords":["perf","perf:responsiveness","testcase"],"op_sys":"All","last_change_time":"2022-10-10T22:59:55Z","creation_time":"2010-06-29T14:36:04Z","summary":"{inc} Resizing window is slow for long list with multicol (from \"-moz-column-count: 3\" or \"column-width: 20em;\")","status":"NEW","id":575614,"priority":"--","severity":"S3"},{"component":"XPConnect","last_change_time":"2025-03-11T08:46:07Z","op_sys":"macOS","keywords":["perf","perf:pageload"],"summary":"Very slow chrome to content DOM access","creation_time":"2010-11-19T15:34:28Z","severity":"S3","priority":"--","id":613498,"status":"NEW"},{"component":"Widget","keywords":["perf","perf:resource-use"],"op_sys":"Linux","last_change_time":"2022-10-10T23:24:13Z","creation_time":"2011-03-31T18:37:55Z","summary":"throttle animation in completely obscured windows (virtual desktop, minimised, hidden behind other fullscreened windows)","status":"NEW","id":646937,"severity":"S3","priority":"P3"},{"component":"Places","op_sys":"All","last_change_time":"2025-09-29T14:01:38Z","keywords":["perf","perf:responsiveness"],"summary":"Repeated calls to location.hash = \"#foo\" cause large amounts of disk activity","creation_time":"2011-06-02T18:09:59Z","severity":"S3","priority":"P3","status":"NEW","id":661590},{"status":"NEW","id":711924,"severity":"S3","priority":"--","creation_time":"2011-12-19T09:05:20Z","summary":"Compositing/present still hapens when the only changing parts are out of the viewport","keywords":["perf","perf:resource-use"],"op_sys":"All","last_change_time":"2024-04-08T16:58:41Z","component":"Graphics: WebRender"},{"id":760888,"status":"NEW","priority":"--","severity":"S3","creation_time":"2012-06-03T03:18:54Z","summary":"IE10 Test Drive: ParticleAcceleration Canvas 2D demo is slow","keywords":["perf"],"last_change_time":"2024-04-05T11:37:58Z","op_sys":"All","component":"Graphics: Canvas2D"},{"id":803709,"status":"NEW","severity":"S3","priority":"P3","creation_time":"2012-10-19T21:25:22Z","summary":"We appear to be copying large data URIs over and over in nsSimpleURI.","keywords":["perf:resource-use"],"op_sys":"All","last_change_time":"2023-06-05T16:31:57Z","component":"Networking"},{"last_change_time":"2025-03-31T14:05:54Z","op_sys":"Linux","keywords":["perf:responsiveness"],"component":"PDF Viewer","severity":"S3","priority":"P3","status":"NEW","id":810214,"summary":"Processing http://lib.tkk.fi/Dipl/2002/urn007413.pdf is slow, and its text layer is all messed up","creation_time":"2012-11-09T08:29:30Z"},{"creation_time":"2012-12-14T13:46:12Z","summary":"janky Scrolling on smartsheet.com Sheets","id":821693,"status":"NEW","priority":"--","severity":"S3","component":"CSS Parsing and Computation","keywords":["perf","perf:responsiveness"],"last_change_time":"2023-03-01T12:04:23Z","op_sys":"Windows 7"},{"op_sys":"Windows 7","last_change_time":"2022-11-24T06:34:31Z","keywords":["perf"],"component":"Graphics: ImageLib","severity":"S3","priority":"--","status":"NEW","id":827440,"summary":"nsIconChannel::AsyncOpen can block","creation_time":"2013-01-07T19:06:03Z"},{"priority":"--","severity":"S3","id":827937,"status":"NEW","summary":"Opening huge mercurial long commit page freezing Firefox","creation_time":"2013-01-08T19:17:33Z","op_sys":"Windows 8","last_change_time":"2022-10-29T12:12:42Z","keywords":["perf"],"component":"Layout"},{"priority":"P3","severity":"S3","status":"NEW","id":830504,"summary":"Firefox should abort on tryserver when executing SQL on the main thread","creation_time":"2013-01-14T22:07:19Z","last_change_time":"2024-08-20T19:28:43Z","op_sys":"All","keywords":["perf:frontend","perf:responsiveness"],"component":"SQLite and Embedded Database Bindings"},{"keywords":["main-thread-io","perf:frontend"],"op_sys":"All","last_change_time":"2023-05-16T02:22:53Z","component":"General","status":"NEW","id":837989,"priority":"--","severity":"S3","creation_time":"2013-02-05T02:16:08Z","summary":"Use IOUtils for gLastOpenDirectory"},{"id":862383,"status":"NEW","severity":"S3","priority":"P3","creation_time":"2013-04-16T15:29:21Z","summary":"nsFileChannel::nsFileChannel causes expensive lstats","keywords":["main-thread-io","perf:responsiveness"],"last_change_time":"2024-03-27T16:10:09Z","op_sys":"macOS","component":"Networking: File"},{"creation_time":"2013-07-07T15:57:11Z","summary":"nsIOService::NewFileURI is doing main thread IO and causes jank","status":"NEW","id":890712,"priority":"P3","severity":"S3","component":"Networking","keywords":["main-thread-io","perf","perf:frontend"],"last_change_time":"2024-04-01T16:26:36Z","op_sys":"All"},{"component":"Layout","op_sys":"All","last_change_time":"2023-07-27T07:06:57Z","keywords":["perf"],"summary":"Polygon.com page scrolling becomes extremely slow after a while","creation_time":"2013-09-10T12:49:00Z","priority":"--","severity":"S3","id":914595,"status":"NEW"},{"component":"General","keywords":["perf:resource-use"],"last_change_time":"2022-10-11T01:07:35Z","op_sys":"All","creation_time":"2013-09-17T02:34:03Z","summary":"Visibility state is not updated when the browser window is obscured or on another workspace","id":917090,"status":"NEW","priority":"--","severity":"S3"},{"id":984690,"status":"NEW","priority":"--","severity":"S3","creation_time":"2014-03-18T00:14:52Z","summary":"Optimize GetRootPresContext() to avoid going through the viewmanager / view tree","keywords":["perf"],"op_sys":"Linux","last_change_time":"2025-12-02T04:57:52Z","component":"Layout"},{"creation_time":"2014-06-10T10:02:00Z","summary":"Preload panel contents on hover of toolbar button","id":1023152,"status":"NEW","severity":"S3","priority":"--","component":"Toolbars and Customization","keywords":["perf:frontend"],"op_sys":"All","last_change_time":"2023-07-19T04:52:40Z"},{"priority":"P3","severity":"S3","id":1047817,"status":"NEW","summary":"Make bookmarks toolbar view use async openContainer","creation_time":"2014-08-02T09:50:40Z","last_change_time":"2026-05-29T15:38:01Z","op_sys":"All","keywords":["perf:frontend"],"component":"Places"},{"last_change_time":"2022-10-11T15:57:30Z","op_sys":"Android","keywords":["perf"],"component":"JavaScript Engine","severity":"S3","priority":"--","status":"NEW","id":1097376,"summary":"Poor performance in Ember app Discourse","creation_time":"2014-11-12T00:22:19Z"},{"component":"Layout: Form Controls","keywords":["multiprocess","perf","perf:responsiveness","testcase"],"op_sys":"All","last_change_time":"2025-12-05T02:06:49Z","creation_time":"2015-01-06T01:55:10Z","summary":"[e10s] There is a delay for about 1 seconds to display <select> drop-down list with 1600+ items","id":1118086,"status":"NEW","priority":"P5","severity":"S3"},{"severity":"S3","priority":"--","id":1154987,"status":"NEW","summary":"[Meta] Move JS parsing off of main thread and enable incremental parsing","creation_time":"2015-04-15T23:32:29Z","last_change_time":"2026-04-07T07:26:45Z","op_sys":"Windows 8.1","keywords":["meta","perf"],"component":"JavaScript Engine"},{"creation_time":"2015-04-16T18:22:07Z","summary":"Very laggy panning and zooming of map on Orbis website","status":"NEW","id":1155307,"severity":"S3","priority":"--","component":"Graphics: WebRender","keywords":["perf:animation","perf:responsiveness","reproducible"],"last_change_time":"2024-04-02T23:00:44Z","op_sys":"All"},{"summary":"ES6 Map performance for large numbers of elements is deficient","creation_time":"2015-05-07T18:46:57Z","priority":"--","severity":"S3","id":1162665,"status":"NEW","component":"JavaScript: GC","op_sys":"Unspecified","last_change_time":"2025-03-12T05:36:53Z","keywords":[]},{"keywords":["perf:responsiveness"],"op_sys":"Unspecified","last_change_time":"2023-02-19T05:13:03Z","component":"DOM: Animation","status":"NEW","id":1213513,"severity":"S3","priority":"--","creation_time":"2015-10-10T00:31:34Z","summary":"2D canvas+HTML/CSS animation demo site broken on Firefox, works great on Chrome"},{"component":"Layout","op_sys":"All","last_change_time":"2024-09-22T12:08:26Z","keywords":[],"summary":"On/Off opacity changes shouldn't create active layers","creation_time":"2015-10-23T09:20:20Z","severity":"S3","priority":"--","id":1217748,"status":"NEW"},{"creation_time":"2015-11-05T17:44:28Z","summary":"Block JavaScript parser thread when source code characters are not available","id":1222086,"status":"NEW","severity":"S3","priority":"--","component":"JavaScript Engine","keywords":["perf"],"last_change_time":"2022-10-11T17:46:56Z","op_sys":"Unspecified"},{"status":"NEW","id":1246410,"severity":"S3","priority":"P3","creation_time":"2016-02-06T17:43:25Z","summary":"Low performance of texImage2D with canvas2d and WebGL","keywords":["perf","regression","testcase"],"op_sys":"Unspecified","last_change_time":"2025-04-05T10:12:20Z","component":"Graphics: CanvasWebGL"},{"op_sys":"Unspecified","last_change_time":"2025-03-17T20:05:29Z","keywords":["perf:responsiveness","reproducible"],"component":"Graphics: WebRender","priority":"--","severity":"S3","status":"NEW","id":1257910,"summary":"Firefox hangs with 100% CPU usage when scrolling on specific page","creation_time":"2016-03-18T17:34:07Z"},{"last_change_time":"2022-10-11T18:13:31Z","op_sys":"Unspecified","keywords":["perf"],"component":"JavaScript Engine","priority":"--","severity":"S3","id":1265980,"status":"NEW","summary":"Running jasmine is slower than Safari and Chrome","creation_time":"2016-04-20T07:12:37Z"},{"creation_time":"2016-06-07T13:45:20Z","summary":"CanvasRenderingContext2D::DrawImage takes lots of  time when scrolling Google Spreadsheet","id":1278554,"status":"NEW","severity":"S3","priority":"--","component":"Graphics: Canvas2D","keywords":["perf"],"op_sys":"Unspecified","last_change_time":"2022-11-08T00:01:53Z"},{"component":"JavaScript: GC","last_change_time":"2024-08-11T09:37:57Z","op_sys":"Unspecified","keywords":["perf"],"summary":"Angular framework performance test spends 10% in nursery GC","creation_time":"2016-06-19T13:43:03Z","priority":"P3","severity":"S3","status":"NEW","id":1280802},{"keywords":["perf:responsiveness","regression"],"op_sys":"Linux","last_change_time":"2022-12-08T15:45:06Z","component":"Graphics","id":1283089,"status":"NEW","severity":"S3","priority":"P3","creation_time":"2016-06-29T13:06:59Z","summary":"Firefox 40+ are very sluggish through x2go"},{"last_change_time":"2026-06-10T12:53:35Z","op_sys":"Unspecified","keywords":["perf"],"component":"Layout","priority":"P3","severity":"S3","status":"NEW","id":1294625,"summary":"Try to tick refresh driver during html parsing","creation_time":"2016-08-12T05:51:58Z"},{"component":"Layout","keywords":["perf"],"last_change_time":"2022-10-11T18:31:41Z","op_sys":"Unspecified","creation_time":"2016-08-18T03:04:45Z","summary":"Measure and solve sync reflow for studying gdoc performance.","id":1296161,"status":"NEW","severity":"S3","priority":"P3"},{"component":"Widget: Win32","keywords":["perf"],"last_change_time":"2026-02-17T17:22:57Z","op_sys":"Windows 7","creation_time":"2016-10-01T23:51:50Z","summary":"If you set a high Polling Rate USB port of the mouse (1000 Hz), there will be noticeable performance issues while moving tabs","status":"NEW","id":1306925,"severity":"S3","priority":"--"},{"component":"General","last_change_time":"2024-08-14T04:57:13Z","op_sys":"Linux","keywords":["perf"],"summary":"[Perf] [google docs] Firefox will get 3~9% faster when running gdoc test cases with chrome user agent","creation_time":"2016-10-03T03:00:35Z","priority":"--","severity":"S3","id":1307024,"status":"NEW"},{"summary":"for background tabs, break refresh driver tick into multiple events off the main thread's event loop","creation_time":"2016-10-08T00:18:22Z","severity":"--","priority":"--","id":1308660,"status":"NEW","component":"Layout","op_sys":"Unspecified","last_change_time":"2025-04-16T19:29:34Z","keywords":["perf","perf:responsiveness"]},{"summary":"Google Apps extremely slow -- scrolling, updating text, etc -- unusable","creation_time":"2016-11-11T14:41:11Z","priority":"P5","severity":"S3","id":1316864,"status":"NEW","component":"JavaScript Engine","op_sys":"Windows 10","last_change_time":"2022-10-11T18:44:06Z","keywords":["perf"]},{"component":"Bookmarks & History","keywords":["hang","meta","nightly-community","perf:frontend"],"op_sys":"All","last_change_time":"2025-03-11T08:30:57Z","creation_time":"2016-11-27T11:13:21Z","summary":"[meta] Speed and performance of importing bookmarks from JSON or HTML files is awful","status":"NEW","id":1320534,"priority":"P5","severity":"--"},{"creation_time":"2017-01-11T03:23:20Z","summary":"DisplayList building shows signs of poor CPU usage","id":1330187,"status":"NEW","severity":"S3","priority":"P3","component":"Layout","keywords":["perf:resource-use"],"op_sys":"Unspecified","last_change_time":"2025-03-11T07:51:38Z"},{"summary":"Explore using the presshell arena for FramePropertyTable","creation_time":"2017-01-12T08:37:41Z","priority":"P3","severity":"S3","status":"NEW","id":1330558,"component":"Layout","op_sys":"Unspecified","last_change_time":"2022-10-11T18:55:13Z","keywords":["perf:resource-use"]},{"component":"Graphics: Layers","keywords":["hang","perf"],"op_sys":"Unspecified","last_change_time":"2022-10-11T18:58:09Z","creation_time":"2017-01-27T21:15:19Z","summary":"PCompositorBridge::Msg_WillClose can block the UI thread when closing a window","id":1334655,"status":"NEW","severity":"S3","priority":"P3"},{"component":"Graphics","op_sys":"Unspecified","last_change_time":"2022-10-11T19:02:26Z","keywords":["perf"],"summary":"Slow performance at drawing rectangles on Google Slides","creation_time":"2017-02-22T22:05:51Z","severity":"S3","priority":"P3","id":1341882,"status":"NEW"},{"summary":"Speed up PHttpChannelConstructor and consider streaming HttpChannelOpenArgs","creation_time":"2017-02-25T04:45:01Z","priority":"P3","severity":"S3","id":1342632,"status":"NEW","component":"Networking: HTTP","op_sys":"Unspecified","last_change_time":"2022-03-02T15:55:52Z","keywords":["perf"]},{"id":1343383,"status":"NEW","priority":"P3","severity":"S3","creation_time":"2017-02-28T23:07:56Z","summary":"nsIDOMWindowUtils::StartFrameTimeRecording should not use sync IPC","keywords":["perf"],"op_sys":"Unspecified","last_change_time":"2022-10-11T19:03:23Z","component":"Graphics: Layers"},{"severity":"S3","priority":"--","id":1343538,"status":"NEW","summary":"Overpainting on Google docs","creation_time":"2017-03-01T15:26:14Z","op_sys":"Unspecified","last_change_time":"2024-11-22T02:22:00Z","keywords":["perf","perf:responsiveness"],"component":"Web Painting"},{"op_sys":"All","last_change_time":"2025-04-30T01:31:39Z","keywords":["perf"],"component":"JavaScript Engine: JIT","severity":"S3","priority":"P3","id":1346178,"status":"NEW","summary":"Consider compiling Ion IC code less eagerly","creation_time":"2017-03-10T12:17:59Z"},{"id":1346927,"status":"NEW","severity":"S3","priority":"--","creation_time":"2017-03-13T20:32:12Z","summary":"Replace PVRManager::GetSensorState with lock-free shared memory structure (Eliminating message queue IPC)","keywords":["perf"],"op_sys":"Unspecified","last_change_time":"2022-10-11T19:05:40Z","component":"WebVR"},{"creation_time":"2017-03-16T09:28:24Z","summary":"Consider storing hints during syntax parse","id":1347861,"status":"NEW","severity":"S3","priority":"P5","component":"JavaScript Engine","keywords":["perf"],"op_sys":"Unspecified","last_change_time":"2022-10-11T19:06:12Z"},{"component":"Layout","op_sys":"All","last_change_time":"2023-11-27T10:28:31Z","keywords":["perf"],"summary":"Optimize away OverflowAreasProperty more often","creation_time":"2017-03-19T22:26:30Z","priority":"--","severity":"S3","status":"NEW","id":1348697},{"id":1349148,"status":"NEW","priority":"P3","severity":"S3","creation_time":"2017-03-21T09:28:43Z","summary":"Improve performance of megamorphic stubs","keywords":["perf"],"op_sys":"All","last_change_time":"2024-04-24T02:40:50Z","component":"JavaScript Engine: JIT"},{"severity":"S3","priority":"P3","status":"NEW","id":1350367,"summary":"Make service worker ScriptLoader paths use cached js bytecode from cache API","creation_time":"2017-03-24T15:40:46Z","last_change_time":"2022-10-11T19:08:05Z","op_sys":"Unspecified","keywords":["perf"],"component":"DOM: Service Workers"},{"creation_time":"2017-03-25T15:19:03Z","summary":"Avoid full session history collect for DOMTitleChanged/OnHistoryReload","id":1350569,"status":"NEW","severity":"S3","priority":"--","component":"Session Restore","keywords":["perf:frontend"],"op_sys":"Unspecified","last_change_time":"2023-07-19T04:57:18Z"},{"component":"Audio/Video: Playback","keywords":["perf"],"last_change_time":"2022-10-11T19:08:17Z","op_sys":"Unspecified","creation_time":"2017-03-25T21:49:47Z","summary":"Bad performance on Sony Horizon game page","status":"NEW","id":1350618,"priority":"P3","severity":"S3"},{"component":"General","last_change_time":"2022-10-11T19:08:21Z","op_sys":"Unspecified","keywords":["perf"],"summary":"Add some instrumentation to find commonly added preference observers","creation_time":"2017-03-26T21:54:08Z","severity":"S3","priority":"--","status":"NEW","id":1350749},{"keywords":["nightly-community","perf","perf:resource-use","power"],"last_change_time":"2025-03-11T08:37:03Z","op_sys":"All","component":"Performance: General","id":1351755,"status":"NEW","severity":"--","priority":"--","creation_time":"2017-03-29T17:44:37Z","summary":"Provide \"Slight/Light/Low power/Battery saving/Battery saver\" mode option"},{"severity":"S3","priority":"P3","id":1351789,"status":"NEW","summary":"Add Telemetry probes for measuring garbage volume per GC","creation_time":"2017-03-29T18:30:44Z","op_sys":"Unspecified","last_change_time":"2025-04-27T11:43:06Z","keywords":["perf"],"component":"JavaScript: GC"},{"creation_time":"2017-03-29T20:02:58Z","summary":"Consider faster alternatives to PLDHashTable in hot Layout code paths","status":"NEW","id":1351829,"severity":"S3","priority":"--","component":"Layout","keywords":["perf"],"last_change_time":"2022-10-11T19:09:06Z","op_sys":"All"},{"summary":"Consider adding StyleDisplay() values to nsIFrame","creation_time":"2017-03-29T20:09:00Z","priority":"--","severity":"S3","status":"NEW","id":1351830,"component":"Layout","op_sys":"All","last_change_time":"2025-05-05T12:26:28Z","keywords":["perf"]},{"priority":"P2","severity":"--","id":1352205,"status":"NEW","summary":"Avoid running the refresh driver when the page is in background","creation_time":"2017-03-30T20:21:31Z","op_sys":"Unspecified","last_change_time":"2022-11-02T13:08:34Z","keywords":["perf","perf:resource-use"],"component":"Layout"},{"component":"JavaScript: GC","op_sys":"Unspecified","last_change_time":"2025-05-06T16:14:08Z","keywords":["meta","perf"],"summary":"[meta] Improve GC scheduling","creation_time":"2017-03-31T19:02:50Z","severity":"S3","priority":"P3","status":"NEW","id":1352524},{"component":"JavaScript Engine: JIT","keywords":["perf"],"op_sys":"All","last_change_time":"2025-02-10T18:11:27Z","creation_time":"2017-04-04T14:54:51Z","summary":"Optimize GetName TypeOfNoProperty","status":"NEW","id":1353384,"priority":"P3","severity":"S3"},{"status":"NEW","id":1354945,"priority":"P3","severity":"S3","creation_time":"2017-04-09T22:09:43Z","summary":"Initialize sandbox global properties lazily","keywords":["perf"],"last_change_time":"2022-10-11T19:11:14Z","op_sys":"Unspecified","component":"XPConnect"},{"priority":"P3","severity":"S3","id":1355456,"status":"NEW","summary":"Investigate preparing the next tab on mousedown on the tab close button","creation_time":"2017-04-11T13:02:53Z","op_sys":"Unspecified","last_change_time":"2023-07-19T04:59:14Z","keywords":["perf","perf:frontend","perf:responsiveness"],"component":"Tabbed Browser"},{"priority":"P4","severity":"S3","id":1355459,"status":"NEW","summary":"The last window and the task bar item should disappear immediately on shutdown","creation_time":"2017-04-11T13:07:05Z","last_change_time":"2023-05-16T02:22:12Z","op_sys":"Unspecified","keywords":["perf:frontend"],"component":"General"},{"id":1356532,"status":"NEW","priority":"P3","severity":"S3","creation_time":"2017-04-14T09:29:21Z","summary":"Try avoiding layout flushes in autocomplete::_handleOverflow","keywords":["perf:frontend","perf:responsiveness"],"last_change_time":"2024-03-22T08:25:52Z","op_sys":"Unspecified","component":"Autocomplete"},{"creation_time":"2017-04-14T16:14:15Z","summary":"Rewrite AppConstants.jsm in C++","id":1356594,"status":"NEW","severity":"S3","priority":"P3","component":"General","keywords":["perf:resource-use"],"op_sys":"Unspecified","last_change_time":"2022-10-11T19:12:20Z"},{"component":"Tours","keywords":["perf","perf:frontend","perf:responsiveness"],"op_sys":"Unspecified","last_change_time":"2024-03-22T13:34:58Z","creation_time":"2017-04-19T11:50:56Z","summary":"Uninitializing UITour is expensive","status":"NEW","id":1357710,"priority":"P3","severity":"S3"},{"creation_time":"2017-04-19T16:33:44Z","summary":"Investigate source of memory_pressure event in gecko, and whether to repurpose it","status":"NEW","id":1357810,"priority":"P3","severity":"S3","component":"JavaScript: 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